In a conventional optical system, a lens is generally used for focusing and diffusing a light to zoom an observing object. However, there is an aberration problem of the lens when the object is observed, and the aberration problem may affect the image quality and may even cause deformations or blurred images. In particular, a spherical aberration is produced by projecting a light at a different position of the lens, such that the light is not be focused at the same focal point when it is projected and focused, but a focal plane will be produced instead to cause the aberration problem.
To overcome the aforementioned aberration problem, conventional methods adopt a non-spherical aberration lens or a complex lens to eliminate the aberration, but these technologies are applicable for transparent solid lenses such as glass lenses and inapplicable for non-solid lenses such as liquid lenses.
In a liquid lens, liquid is filled into the liquid lens, such that the liquid can be used to adjust the surface curvature of a film of the lens to constitute a convex lens or a concave lens. The change of the surface curvature provides the function of a variable focus or a variable magnifying power to the liquid lens. However, it is difficult or unable to adjust the surface curvature due to the shape of the lens surface of the conventional liquid lens, and thus a severe spherical aberration may occur at a high magnifying power and a poor image quality may result.
Therefore, it is a main subject of the present invention to provide a method to overcome the poor image caused by the aberration of the liquid lens.